SELECT 
  1 
FROM 
  cscart_lock_keys 
WHERE 
  key_id = '78700ab189947d1afa2d92cc528a64aa2f2a81fe07c937941217169060f48117' 
  AND token = 'AwnChWDNtgD19WOpcJeL1GtH+LNZ4ikHQEPUw8oKu28=' 
  AND expiry_at > UNIX_TIMESTAMP(NOW())

Query time 0.00047

JSON explain

{
  "query_block": {
    "select_id": 1,
    "table": {
      "message": "Impossible WHERE noticed after reading const tables"
    }
  }
}